|
|
|
BY:
Andy Cornwall and Bill Marchant
Microsoft Netmeeting is a collaboration tool allowing communications between two or more computers in a LAN or over the Internet. Its communications functions include video and voice, whiteboard, text chat, and file transfer. Further, Netmeeting enables remote computer sharing and operation. As it turns out, mutually compatible versions of Netmeeting are available for Windows from 98 through XP.
Andy proposed that we try to use NetMeeting between two of our computers over the Internet. We both have Windows XP on at least one of the machine at our respective homes. The problem was, if you look casually for NetMeeting on XP you will not find it, but if you try to download NetMeeting from Microsoft, you will be informed that it is not suitable for Windows XP.
After a bit of research on the web, you discover that NetMeeting already exists in XP. You check Start, then Run. Then you type "conf" into the edit box and hit OK. The NetMeeting window comes up. What is more, if you check the About Box, you discover that it is version 3.01, this is what the message told you needed when the downloaded version was not suitable for XP.
Netmeeting has two ways to set up a link between computers via the Internet. One is through a central directory where all computers wanting to join in a session sign on to make contact. By default the Microsoft Directory is already incorporated in Netmeeting.
Bill tried to get a registration on the Microsoft Directory. This proved to be a problem. During the process, there was always a message saying the directory ( called an ILS) could not be found. Again, more web searching revealed that Microsoft no longer runs its directory. And then Bill discovered further advice on another web page, to the effect that no-one should register on a directory, Microsoft's or any other. Later we concluded that this probably provided a security hole which other unsavoury folks might exploit.
The second way to link computers is by Internet IP address, but this works for connecting only two computers. Both computers must be running NetMeeting. One computer initiates a call by having the Internet IP address of the other entered in its Netmeeting's address box.
To make a computer-to-computer link, one of us needed the IP address of the other's Internet modem in order to make a call. We each have a LAN router that attaches to our Internet modems, and this created another layer of complexity. Every computer plugged into the router (or running wireless), and the router itself, has an internal-LAN IP address. The Internet modem, on the other hand, has its own, different IP address for Internet communications. The Internet IP address is allocated by the Internet service provider. Andy found that by using a webpage browser (in this case Firefox) to query his router with its own LAN IP address (192.168.0.1 for Linksys routers), there is a 'Status' tab showing the IP address allocated to him by his service provider. He gave the number to Bill over the phone (an e-mail message would have worked as well), who entered it in NetMeeting's call box on his computer, but was unable to connect.
This problem was solved when Andy remembered something that Dave Potter had mentioned at a Club meeting some time ago. NetMeeting needs to be able to call a specific computer on a LAN, but we both have LANs with more than one machine. Dave talked about something called a "DMZ" in a router to identify a computer on the LAN that would 'take on' the Internet IP address recognized by the router / Internet modem and at the same time by-pass any of the router's firewall packet restrictions. Back to the modem again. Under the 'Advanced' tab (in Linksys), a button labeled DMZ reveals itself. This allows the user to specify one machine to be put into the DMZ. The DMZ feature needs to be enabled for Netmeeting to work with a computer on the LAN.
NetMeeting worked for us. We were able to get two way video pictures (of each other) using our web cameras. We set up a whiteboard which we both had access to, and we had two way audio through microphones and speakers. A program on Andy's machine was operated successfully from Bill's machine, and both of us could see what was happening. Control of the program could be transferred back and forth by the person at the computer which held the program, in this case Andy.
At the club meeting 28 October, Andy demonstrated NetMeeting with two computers using a wireless LAN. Other experiments done there showed that one could type on the whiteboard. Altogether, a very successful experiment.
